


I Saw Cu Chulainn Kissing Santa Claus

by hovercraft



Category: Fate/Grand Order, Fate/stay night & Related Fandoms
Genre: Crack Treated Seriously, Kisses, M/M, all I want for next christmas is Santa Dia, rein-dogs
Language: English
Status: Completed
Published: 2020-12-19
Updated: 2020-12-19
Packaged: 2021-03-10 18:15:25
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,546
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28171521
Author URL: https://archiveofourown.org/users/hovercraft/pseuds/hovercraft
Summary: In which Diarmuid is decided to be Santa for the year.(Absolutely a crackfic, but hopefully a cute one.)
Relationships: Diarmuid Ua Duibhne | Lancer/Every Single Cu
Comments: 10
Kudos: 28





	I Saw Cu Chulainn Kissing Santa Claus

**Author's Note:**

> this is for my bestie!!

Karna had passed the mantle onto him with little ceremony, but with the demand and faith that Diarmuid would be able to do the job of ‘Santa’ correctly. To make magic for servants and their master, and especially for the young ones by carrying on the spirit of Christmas. Diarmuid was about to ask, well, _why him._ Surely his Saber counterpart would be more festive? Though the job did seem appealing— it was a coveted title that servants had fought for in the past. Karna just said ‘I trust you’ and that was that.

His spirit origin had changed, and like that, the Lancer Diarmuid was now a Caster.

He winced at his sudden change, wondering why a Caster of all things when Santas were pitted against trial after trial and he was saddled with the weakest class. He felt his hair in the back of his head— it had grown somewhat longer underneath the comically oversized Santa hat. His outfit now had gold, white, and red tones all over it. Nonetheless, he was determined… despite being a little concerned about all of this. This year, maybe he could prove himself just as worthy as any other servant, even as a caster.

Fionn took one look at him upon entering the room and _laughed_ so hard he wheezed, having to leave the room to catch his breath.

Bitterly, Diarmuid closed his eyes and thought, “What kind of mess is this going to be?”

—

“Well, a Santa needs reindeer!”

Jack and Nursery Rhyme were helping him get acquainted with the legend of Santa.

“I don’t know where we’re going to find reindeer in Chaldea…”

“Anything can be a reindeer if you try hard enough.”

“???” What on Earth did that mean?

Cu Chulainn, as well as his caster self, had popped into the room to see how Diarmuid was handling his new mantle. “You know a new Singularity has popped up, right? Master needs you.”

“Right… ah…”

“He can’t!” Jack cried out. “Not without his reindeer!”

“I don’t think the other Santas had reindeer…”

Cu tittered, crossing his arms and leaning on the doorway. “She’s right, the rest were rule-breakers. So what are you going to do, Santa?”

Cu always had a penchant for teasing him, and for some reason, it always warmed Diarmuid up. It was different from Fionn’s teasing, and he welcomed it. Before Diarmuid could say anything, Nursery Rhyme had a suggestion.

“Rein-dogs!”

“…?” Diarmuid looked at her, inquisitively.

“There are four Cu’s! Why don’t you make them your reindeer? You’ll need people to fight alongside you during the singularity, after all…”

Diarmuid sputtered. “They would not take kindly to—”

“Sounds like fun,” Caster said. “I’m in.”

Cu shot him a look. “Oi, just because you’re me doesn’t mean you get to rope me into things like this—”

“Why not? We’ll just help him fight. It’s not like they’re making us wear bands with antlers on them.”

“…” Cu put his hand on his neck and cracked it, slightly. “I guess I’ve been getting restless… but don’t call us rein-dogs. Got it? I’ll see if the other me and the berserker want to join us.”

Diarmuid averted his eyes, hard. The berserker Cu had always acted strangely around him, and he always thought it was because he was usually so weak. He made awkward conversation around him, and he felt their relationship get worse with every conversation— which would be fine if Diarmuid didn’t have a physical crush on the man. All of the Cu’s, really… were sort of his type, but it’d be a cold day in Hell before he admitted it (which it had literally been, a few years ago when Altera was Santa). To be surrounded by all of them, could he really handle it?

He had no doubt the berserker would say ‘no’ anyway, so imagine his surprise when he and the young Cu showed up to the meeting room.

All four of them.

Apparently, Nursery Rhyme had cornered them with gifts of antler hats and threatened tears if they wouldn’t wear them, and Emiya was watching, so it had been a done deal.

“Four rein-dogs, at your service.” Caster smirked ruefully.

“ _Stop_ it,” The original Cu emphasized.

“What are we dealing with?” Diarmuid asked Da Vinci, quickly trying to change the subject and not do something embarrassing like laugh.

“Well, you’re going to home territory. The singularity is in Ireland. A fae servant showed up… she’s causing trouble for all the locals in a little bubble of a singularity. Think you can handle it before Santa is supposed to deliver his gifts?”

“Of course.” Diarmuid stood proud, despite his doubts.

“Good, because we’re working under a time limit! Get ready.”

—

The fae servant would turn out to be a nightmare to deal with.

While it was wonderful to be back in his homeland, monsters were everywhere, apparently, the servant hadn’t been paid tribute in the way they wanted, so they stole the Christmas Grail and was using its power to raise all sorts of havoc. Diarmuid prayed quietly to himself that whatever it was, it better not be someone he recognized, damn it all—

It was only a few nights before Christmas, and he had to be back to Chaldea as soon as he solved this mess. Without his twin spears, he felt weaker than usual, but the magic he could cast using runes— unusual in and of itself, presents and ribbon and toys colliding with monsters, was more than suitable for the task. He and the four Cu’s were making decent headway, too.

“Well— what are you getting us for Christmas, Santa?”

Caster was being playful between fights.

“I— you’ll get my thanks, and I’ll see what I can grant you with these new powers…” Diarmuid paused. “What would you want, anyway? I didn’t really peg you guys for the ‘wanting things for Christmas’ type.”

“That’s your job, isn’t it?” Cu spoke, and Diarmuid was a bit envious he still had his spear. “To pick out the best gift for all of us. You’re perceptive, Diarmuid, I’m sure you have some idea.”

Diarmuid had ideas for just about everyone. A weight rack for Quetzalcoatl, a modern and expensive cooking set for Emiya and Tamamo Cat, a completely restocked medical wing for Nightingale, who would accept nothing else— but to his horror, he had no idea what _any_ Cu would want. Spear polish? Oh my god, think of a worse gift, why don’t you? Sweets from their era, a new fishing pole, something… something, something, something, he had no clue.

But all of the Cu’s knew exactly what they wanted.

—

More fights, more grinding the lottery for Ritsuka, more of everything.

Diarmuid still couldn’t think of what to get them.

Even when they defeated the big bad— a disgruntled fae version of Medb, who else?—he still hadn’t thought of a single thing for the people who helped him the most. As hard as he tried, he couldn’t think of a single thing.

So he decided to ask.

—

The servants were celebrating back in Chaldea and Diarmuid was just about done handing out presents when he stopped by the table of Cu Chulainn's, who were drinking and chatting about whatever it was you spoke to your alternate selves about. He sighed, confessing that he didn’t know what they wanted.

Silence, then a snicker.

“It’s not obvious…?” Caster leaned on his hand, smirking softly.

“I’m afraid not, I tried to think of something, and—”

The original Cu Chulainn grabbed Diarmuid by the tassels of his decorative cloak and dragged him down for a kiss. Diarmuid was stunned silent, unsure of what to say, so Cu brusquely took advantage of that to steal that kiss for just a few moments longer.

“You haven’t noticed you’re exactly our type? How we always volunteer to fight when you’re on the field? … Even the big guy?”

Berserker said nothing, but his silence spoke more for agreement than disagreeing.

“… even the one from the other universe?”

“Yeah, him too.”

“… I, uh… I do owe you my thanks for helping me—”

Caster took it as permission to take his next, surprising him yet again in a stolen smooch. He could barely get a word out when Prototype did the exact same thing. It was overwhelming, to say the least, and he hoped no one was staring.

(Everyone was staring.)

Finally, he looked to Cu Alter, who had been relatively quiet for all of this, and as Diarmuid approached him, he quietly stammered, “I can give you something you’d rather have, I’m sure—”

“This is what I want.”

Cu Alter, rougher than his counterparts, pulled him down for a more invasive kiss than the other three had dared. He only let him go once he’d had his fill, and Diarmuid was thoroughly red. All four of them were looking at him with… amusement and expectation, some combination of the two. Diarmuid tried to say something when he realized he hadn’t handed over the grail to Da Vinci.

“I have to— official Santa business. You understand, yes?”

Cu laughed. “Sure, but come back before the party is over.”

Diarmuid nodded, wondering what the hell he was going to do with four different Cu’s vying for his attention once he got back.


End file.
